Typically, an asphalt paving machine includes a material feed system installed thereon. The material feed system may feed asphalt from a hopper portion of the machine to one or more augers for spreading the asphalt on a ground surface. The material feed system may generally include a left mechanism and a right mechanism, such that each of the left mechanism and the right mechanism may include a conveyor and an auger. Also, each of the left mechanism and the right mechanism may include one or more sensors associated therewith. In some instances, the material feed system may be configured to be operated in an automated or semi-automated manner utilizing the one or more sensors associated with the left mechanism and the right mechanism. This automated mode may utilize two, four, or some other number of sensors to control an operation of the material feed system. Alternately, the material feed system may be operated in a manual mode in which no sensors may be utilized.
However, in many situations, when one of the sensors of either the left mechanism or the right mechanism may be damaged, an operator may be forced to operate the material feed system in the manual mode. This zero-sensor mode represents a full manual mode of operation, such that each of the left mechanism and the right mechanism may be operated manually by the operator. However, the zero-sensor mode of operation may result in increased operator intervention, increased operator dependence, increased operator fatigue, increased fluctuation in mat depth and smoothness, reduced product quality, and the like. Hence, there is a need for an improved configuration of the material feed system for such paving machines.
U.S. Pat. No. 3,967,912 describes a control means for independently driving two feed conveyors and two spreader augers each by its own drive motor. The control means for each feed conveyor includes a sensor at a discharge end of the feed conveyor and means responsive to changes in a level of a paving material at the sensor for proportionally increasing a drive speed of the conveyor as the level drops and proportionally decreasing the drive speed of the conveyor as the level rises. The control means for each auger includes a sensor adjacent a discharge end of the auger and means responsive to changes in a level of the paving material at the sensor for proportionally increasing a drive speed of the auger as the level drops and proportionally decreasing the drive speed of the auger as the level rises.